Material Removal Rate Control in Open-Air Type Plasma Chemical Vaporization Machining by Pulse Width Modulation of Applied Power

2014 ◽  
Vol 625 ◽  
pp. 593-596
Author(s):  
Yoshiki Takeda ◽  
Yuki Hata ◽  
Katsuyoshi Endo ◽  
Kazuya Yamamura
Keyword(s):  
Material Removal Rate ◽  
Pulse Width ◽  
Material Removal ◽  
Pulse Width Modulation ◽  
Removal Rate ◽  
Scanning Speed ◽  
Control Mode ◽  
Pwm Control ◽  
Rf Power ◽  
Plasma Chemical

Plasma chemical vaporization machining (PCVM) is an ultraprecise figuring technique for optical components without introducing the subsurface damage. In our previous study, the material removal volume was controlled by changing the scanning speed of the worktable. However, because of inertia of the worktable, a discrepancy between the theoretical scanning speed and the actual scanning speed will occur if the spatial change rate of speed is rapid. Therefore, we proposed the application of the pulse width modulation (PWM) control and the amplitude modulation (AM) control of the applied RF power to control the material removal rate (MRR). Experimental results showed that the relationship between the MRR and the average RF power had high linearity, the control range of the PWM control mode was from 0.19 x 10-2 mm3/min to 3.90 x 10-2 mm3/min (from 5% to 100%), which was much wider than that of the AM control mode.

Material Removal Rate Control in Open-Air Type Plasma Chemical Vaporization Machining Using Optical Actinometry

2012 ◽  
Vol 523-524 ◽  
pp. 267-271
Author(s):  
Yuto Yamamoto ◽  
Yuki Hata ◽  
Mao Hosoda ◽  
Yasushi Oshikane ◽  
Kazuya Yamamura
Keyword(s):  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Optical Emission ◽  
Functional Materials ◽  
Scanning Speed ◽  
Atomic Density ◽  
Plasma Chemical ◽  
Shape Accuracy ◽  
Ultra Precision

Open-air type numerically controlled plasma chemical vaporization machining (NC-PCVM) is promising technique to fabricate the ultra-precision optical components and to finish the functional materials. The objective shape is fabricated by controlling the scanning speed of the localized plasma because removal volume is proportional to the dwelling time of the plasma on the workpiece surface. To achieve deterministic figuring with shape accuracy of nanometer level, it is essential to keep volumetric material removal rate (MRR) constant during and batch to batch processing. The removal rate is proportional to the density of fluorine radical generated by plasma. So, we control the electric power to keep the removal rate constant during the process based on the fluorine atomic density obtained by optical emission actinometry. We report the relationship between MRR and fluorine atomic density measured by optical emission actinometry.

scholarly journals Optimization of Laser Engraving of Acrylic Plastics from the Perspective of Energy Consumption, CO2 Emission and Removal Rate

2021 ◽  
Vol 5 (3) ◽  
pp. 78
Author(s):  
Mohammad Muhshin Aziz Khan ◽  
Shanta Saha ◽  
Luca Romoli ◽  
Mehedi Hasan Kibria
Keyword(s):  
Energy Consumption ◽  
Production Rate ◽  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Scanning Speed ◽  
Gas Emissions ◽  
Laser Engraving ◽  
Co2 Gas ◽  
Optimal Set

This paper focuses on optimizing the laser engraving of acrylic plastics to reduce energy consumption and CO2 gas emissions, without hindering the production and material removal rates. In this context, the role of laser engraving parameters on energy consumption, CO2 gas emissions, production rate, and material removal rate was first experimentally investigated. Grey–Taguchi approach was then used to identify an optimal set of process parameters meeting the goal. The scan gap was the most significant factor affecting energy consumption, CO2 gas emissions, and production rate, whereas, compared to other factors, its impact on material removal rate (MRR) was relatively lower. Moreover, the defocal length had a negligible impact on the response variables taken into consideration. With this laser-process-material combination, to achieve the desired goal, the laser must be focused on the surface, and laser power, scanning speed, and scan gap must be set at 44 W, 300 mm/s, and 0.065 mm, respectively.

Parametric Study of Pulsed CO2 Laser Surface Treatment of Alumina Ceramics

2015 ◽  
Vol 15 (3) ◽  
pp. 301-308
Author(s):  
A. Bharatish ◽  
H. N. Narasimha Murthy ◽  
Ajithkumar Radder ◽  
V. Mamatha ◽  
B. Anand ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Material Removal Rate ◽  
Laser Power ◽  
Material Removal ◽  
Removal Rate ◽  
Scanning Speed ◽  
Pulse Frequency ◽  
Alumina Ceramics ◽  
Laser Surface Treatment ◽  
Grey Relational

AbstractThis paper focuses on investigating the influence of laser power, pulse frequency and scanning speed on material removal rate and surface roughness during CO2 laser surface treatment of alumina ceramics. Pulse frequency and laser power were the significant factors influencing the material removal rate and surface roughness, respectively. Adequate response surface models were established to correlate the laser parameters and the measured responses. Grey relational analysis predicted the optimal responses at 90 W laser power, 5 kHz pulse frequency and 400 mm/s scanning speed. Desirability function based Multi objective optimization results indicated that minimum material removal rate (0.5117 mm3/s) and surface roughness (0.5968 µm) are achieved at 90 W laser power, 5 kHz pulse frequency and 337.37 mm/s scanning speed which were in close agreement with Grey Relational results. Increase in homogeneity and smoothness of the laser treated alumina surface along with formation of micro recast particles away from the laser traverse path were evidenced by the SEM micrographs.

Smoothing Mechanism of Reaction Sintered SiC in Plasma Assisted Polishing Using Ceria Abrasive

2012 ◽  
Vol 516 ◽  
pp. 119-124
Author(s):  
Hui Deng ◽  
Masaki Ueda ◽  
Kazuya Yamamura
Keyword(s):  
Material Removal Rate ◽  
Oxidation Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Rf Power ◽  
Plasma Irradiation ◽  
Oxidation Rates ◽  
Mechanism Of Reaction ◽  
Lower Load ◽  
Relationship Of

For the finishing of some difficult-to-machine materials, a novel polishing technique named plasma assisted polishing (PAP) was proposed. Ceria abrasive polishing with different electric power plasma irradiation was conducted on RS-SiC surface. Low RF power plasma (8 W) was used, many protrusions were generated which made the surface roughnesses bad (60.93 nm p-v, 5.51 nm rms). In contrast, the height and amount of protrusions decreased when RF power was increased to 12 W, which made the surface roughness better (31.83 nm p-v, 2.63 nm rms). Also, scratches completely disappeared after PAP. To explain the above results, the relationship of oxidation rate by plasma irradiation and material removal rate by abrasive polishing was taken into consideration. The different compositions in RS-SiC have different oxidation rates and levels of hardness. When the oxidation rate is higher than material removal rate, the heterogeneous polishing of RS-SiC is turned to homogeneous polishing of SiO2, and then a flat surface with an oxide layer can be obtained. To prove the above assumption, we firstly oxidized the surface with plasma irradiation for 1 h, and then PAP with a much lower load was conducted on the oxidized surface for 0.5 h. A scratch-free surface with 12.61 nm p-v and 1.45 nm rms was obtained which coincides with the mechanism we propose.

Research on Electronic Discharge Grinding of Polycrystalline Diamond Based on Response Surface Method

2018 ◽  
Vol 764 ◽  
pp. 123-132 ◽  
Author(s):  
Jia Jun Tang ◽  
Hui Zhang ◽  
Pei Qing Ye ◽  
Chao Hai Wang
Keyword(s):  
Response Surface ◽  
Response Surface Method ◽  
Material Removal Rate ◽  
Rotational Speed ◽  
Pulse Width ◽  
Material Removal ◽  
Removal Rate ◽  
Polycrystalline Diamond ◽  
Grinding Process ◽  
Surface Method

To improve the material removal rate (MRR), the effects of electrode rotational speed, gap voltage and pulse width on the MRR of PCD EDM grinding process were studied. By adding pre-experiments, the optimization process is more rapid. A second-order regression model of MRR is established by using response surface method based on Composite Circumscribed design (CCC). And the influence of each parameter on the response is analyzed. The results show that the optimal removal rate is after optimized, which is 11.8% higher than that of the pre-experiment.

Effects of Process Parameters on Surface Roughness and MRR in the hard turning of EN 36 steel

2018 ◽  
pp. 102-110
Author(s):  
Amritpal Singh ◽  
Rakesh Kumar
Keyword(s):  
Surface Roughness ◽  
Material Removal Rate ◽  
Material Removal ◽  
Hard Turning ◽  
Control Parameter ◽  
Removal Rate ◽  
Cutting Speed ◽  
Depth Of Cut ◽  
Cutting Condition ◽  
Dry Cutting

In the present study, Experimental investigation of the effects of various cutting parameters on the response parameters in the hard turning of EN36 steel under the dry cutting condition is done. The input control parameters selected for the present work was the cutting speed, feed and depth of cut. The objective of the present work is to minimize the surface roughness to obtain better surface finish and maximization of material removal rate for better productivity. The design of experiments was done with the help of Taguchi L9 orthogonal array. Analysis of variance (ANOVA) was used to find out the significance of the input parameters on the response parameters. Percentage contribution for each control parameter was calculated using ANOVA with 95 % confidence value. From results, it was observed that feed is the most significant factor for surface roughness and the depth of cut is the most significant control parameter for Material removal rate.

Performance Analysis of Trihexyltetradecylphosphonium Chloride Ionic Fluid under MQL Condition in Hard turning

2020 ◽  
Vol 17 (1) ◽  
pp. 7629-7647
Author(s):  
A. Pandey ◽  
R. Kumar ◽  
A. K. Sahoo ◽  
A. Paul ◽  
A. Panda
Keyword(s):  
Material Removal Rate ◽  
Feed Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Cutting Speed ◽  
Coconut Oil ◽  
Chip Morphology ◽  
Weight Fraction ◽  
Cutting Fluid ◽  
Depth Of Cut

The current research presents an overall performance-based analysis of Trihexyltetradecylphosphonium Chloride [[CH3(CH2)5]P(Cl)(CH2)13CH3] ionic fluid mixed with organic coconut oil (OCO) during turning of hardened D2 steel. The application of cutting fluid on the cutting interface was performed through Minimum Quantity Lubrication (MQL) approach keeping an eye on the detrimental consequences of conventional flood cooling. PVD coated (TiN/TiCN/TiN) cermet tool was employed in the current experimental work. Taguchi’s L9 orthogonal array and TOPSIS are executed to analysis the influences, significance and optimum parameter settings for predefined process parameters. The prime objective of the current work is to analyze the influence of OCO based Trihexyltetradecylphosphonium Chloride ionic fluid on flank wear, surface roughness, material removal rate, and chip morphology. Better quality of finish (Ra = 0.2 to 1.82 µm) was found with 1% weight fraction but it is not sufficient to control the wear growth. Abrasion, chipping, groove wear, and catastrophic tool tip breakage are recognized as foremost tool failure mechanisms. The significance of responses have been studied with the help of probability plots, main effect plots, contour plots, and surface plots and the correlation between the input and output parameters have been analyzed using regression model. Feed rate and depth of cut are equally influenced (48.98%) the surface finish while cutting speed attributed the strongest influence (90.1%). The material removal rate is strongly prejudiced by cutting speed (69.39 %) followed by feed rate (28.94%) whereas chip reduction coefficient is strongly influenced through the depth of cut (63.4%) succeeded by feed (28.8%). TOPSIS significantly optimized the responses with 67.1 % gain in closeness coefficient.

Effect of SiC-Cu Electrode on Material Removal Rate, Tool Wear and Surface Roughness in EDM Process

2020 ◽  
Vol 38 (9A) ◽  
pp. 1406-1413
Author(s):  
Yousif Q. Laibia ◽  
Saad K. Shather
Keyword(s):  
Surface Roughness ◽  
Tool Wear ◽  
Material Removal Rate ◽  
Material Removal ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
304 Stainless Steel ◽  
Tool Electrode ◽  
Pulse Time ◽  
Edm Process

Electrical discharge machining (EDM) is one of the most common non-traditional processes for the manufacture of high precision parts and complex shapes. The EDM process depends on the heat energy between the work material and the tool electrode. This study focused on the material removal rate (MRR), the surface roughness, and tool wear in a 304 stainless steel EDM. The composite electrode consisted of copper (Cu) and silicon carbide (SiC). The current effects imposed on the working material, as well as the pulses that change over time during the experiment. When the current used is (8, 5, 3, 2, 1.5) A, the pulse time used is (12, 25) μs and the size of the space used is (1) mm. Optimum surface roughness under a current of 1.5 A and the pulse time of 25 μs with a maximum MRR of 8 A and the pulse duration of 25 μs.

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